At approximately 6:10 Tuesday morning, Station2 and Rescue Squad 4 were alerted for a vehicle collision with rescue on Hanover Pike. Engine/Tanker 24 and Medic 29 arrived on scene to find three vehicles in the roadway and one patient trapped. After stabilizing the vehicle, the crew from Engine/Tanker 24 began working on extricating the patient. When Rescue Squad 4 arrived, the two crews worked to remove the door and the roof for better access in order to remove the patient from the vehicle. Aviation was requested while extrication was occurring. The initial landing site was to be the former North Carroll High School with Engine 33. However, the proposed landing site was obscured by ground fog and Trooper 3 landed in a parking lot near the accident scene. The patient who was trapped was transported by Trooper 3 to shock trauma while a patient from another vehicle was transported by Medic 49 to Carroll Hospital Center. Four other patients refused treatment and transportation. The scene was left to Maryland State Police for investigation.